There are things which are within our power, and there are things which are beyond our power. Within our power are opinion, aim, desire, aversion, and, in one word, whatever affairs are our own. Beyond our power are body, property, reputation, office, and, in one word, whatever are not properly our own affairs. Now, the things within our power are by nature free, unrestricted, unhindered; but those beyond our power are weak, dependent, restricted, alien.
τῶν ὄντων τὰ μέν ἐστιν ἐφʼ ἡμῖν, τὰ δὲ οὐκ ἐφʼ ἡμῖν. ἐφʼ ἡμῖν μὲν ὑπόληψις, ὁρμή, ὄρεξις, ἔκκλισις καὶ ἑνὶ λόγῳ ὅσα ἡμέτερα ἔργα· οὐκ ἐφʼ ἡμῖν δὲ τὸ σῶμα, ἡ κτῆσις, δόξαι, ἀρχαὶ καὶ ἑνὶ λόγῳ ὅσα οὐχ ἡμέτερα ἔργα. καὶ τὰ μὲν ἐφʼ ἡμῖν ἐστι φύσει ἐλεύθερα, ἀκώλυτα, ἀπαραπόδιστα, τὰ δὲ οὐκ ἐφʼ ἡμῖν ἀσθενῆ, δοῦλα, κωλυτά, ἀλλότρια.
Enchiridion 1.1 – 2